Secret Military Space Plane Primed For Test Launch

A secretive military spacecraft resembling a small space
shuttle orbiter is
undergoing final processing in Florida for launch on April 19.

The Air Force confirmed the critical preflight
milestone in a response to written questions on Thursday.

The 29-foot-long, 15-foot-wide Orbital
Test Vehicle arrived in Cape Canaveral, Fla., last month according to the
Air Force. The OTV spaceplane was built at a Boeing Phantom Works facility in
Southern California.

Managed by the Air Force Rapid Capabilities Office, the OTV
program is shrouded in secrecy, but military officials occasionally release
information on the the spaceplane's progress.

"It is now undergoing spacecraft processing including
checkout, fueling, and encapsulating in the 5-meter fairing of the Atlas 5
[rocket]," an Air Force spokesperson said.

The 11,000-pound vehicle will launch
inside the nose cone of the Atlas 5 rocket. Liftoff is currently set for 10
p.m. EDT on April 19.

The reusable spacecraft is more famously known as the X-37B. The
design is based on the orbital and re-entry demonstrator initially developed by
NASA, then handed over to the Pentagon.

The NASA version of the X-37 featured an equipment bay 7
feet long and 4 feet in diameter for experiments and deployable payloads.

The Defense Advanced Research Projects Agency completed a
series of approach and landing tests in 2007 using the White Knight airplane
from Scaled Composites as a mothership.

It is easy to track the X-37's tumultuous history. NASA
awarded the first X-37 contract to Boeing in July 1999, and the agency flew a
series of visible atmopsheric tests on a scale model of the spaceplane in 2001.
The X-37 began its transformation from a human spaceflight testbed to a
military-run project when NASA shifted responsibility to DARPA in September
2004, a consequence of the space agency's new focus on lunar exploration.

But specific payloads for the Air Force's OTV program aren't
so clear. Officials have denied interview requests on the project, and the
military only releases information through written responses.

The X-37B's mission is to "demonstrate a reliable,
reusable, unmanned space test platform for the United States Air Force,"
the military fact sheet says. "Objectives of the OTV program include space
experimentation, risk reduction and concept of operations development for
reusable space vehicle technologies."

At the end of its mission, the X-37B will fire its engine
and drop from orbit, autonomously navigating through a fiery re-entry on the
way to its 15,000-foot-long primary runway at Vandenberg Air Force Base, Calif.
Edwards Air Force Base is the backup landing site.

The duration of the spaceplane's first mission isn't being
announced.

"The X-37B has the requirement to be on-orbit up to 270
days," the Air Force spokesperson said. "Actual length for the first
mission will depend on the meeting the mission objectives, which consists of
checkout and performance characteristics of the spacecraft systems."